Need help troubleshooting a redirect conflict

I have a site using 8 different forms with the ddfm plugin (https://www.dagondesign.com/) and they had been working fine until we changed the url structure with the use of a redirection plugin (https://urbangiraffe.com/plugins/redirection/).

Now the forms will submit (we receive the email) but the page does not reload with our thank you message. If I disable the redirection plugin, the forms work. I cannot leave the redirection plugin disabled as it affects hundreds of urls that have already been indexed. Is there something I can modify in either plugin to resolve this?

Also, while troubleshooting, I discovered that turning image verification on for the forms doesn’t result in a verification image showing and emails still go through. Not sure if that means anything because it wasn’t being used previously.

Help would be much appreciated.